Gyratory screen



March 16, 1943. w. J. PARKS 2,313,765

GYRATORY S GREEN Original Filed Sept. 7. 1937 2 efls-sheet 1 F 6 z mvsmox (@JM WM March 16, 1943. w J, PARKS 2,313,765

GYRATORY S GREEN Original Filed Sept. 7, 1937 2 Sheets-Sheet 2 III,

1' WALK F1 6.3.

INVENTOR. Mu 725/? J Rik/r:

BY JMWM Patented Mar-.16, 1943 UNITED STATES PATENT OFFICE amass w... I. $112323. Original application September I, 1937, Serial No.

Dividedand this application October 22,- 1940, Serial No. 862,215

'pivotally connected to the four corners of the BOlaims.

The present invention relates to ayratory mechanism particularly adapted for use in screening materials and similar operations. The object of the invention is to provide a system of reciprocating forces which will, by their action on the base frame or supporting structure, balance rotating forces generated inrthe resilient supports of a gyrating screena In my United States Letters Patent No. 2,264,- 769, I have described an invention which comprises the provision of means for balancing the forces generated by the motion of a. gyratory body such as a screen frame, such means consisting essentially of complementary straight line forces. The invention is described as particularly adapted to that type of gyratory screen mechanism wherein theactuating or driving element consists of a drive shaft eccentrically Joumalled at substantially the center of gravity of a resiliently supported screen frame whereby the latter possesses a gyratory motion. I found, in that case, that by means of connecting rods eccentrically connected to the drive shaft in a direction opposite to that of the eccentricity of the screen frame with respect to the center line of the drive shaft, such connecting rods being angularly' disposed with respect to each other so that their lines of effective action were complementary to each other, and that by resiliently supporting both the screen frame and the connecting rods to the base structure or supporting frame, the forces generated by the gyrating screen body and the complementarily disposed connecting rods counter-balance each other to eliminate the transmission of vibrating forces to the supporting frame.

The present invention, which has been divided out of the application resulting in the aforesaid patent, is directed to a modified form of construction embodying the principle of the invention, and will be best understood by reference to the accompanying drawings, wherein Fig. l is a side elevation of the modified form of construction, wherein the screen is pendently supported upon the supporting member;

Fig. 2 is an end eievational view of the apparatus shown in Fig. 1, and

Fig. 3 is an enlarged detail sectional view through the drive shaft assembly, taken on the line 33 of Fig. 1.

Referring more particularly to the drawings, the apparatus is shown to comprise a screen body or frame which is pendently supported from the supporting member or frame 3| by means of the vertical rods 32 and 33 which are screen frame It, as indicated at It and 35 respectively. The upper ends of the rods 32 and 33 are resiliently connected to the-supporting frame 3| by means of the coil springs 36 and 31.

A drive shaft 38 is located substantially at the center of gravity of the screen frame 30 and is eccentrically Journalled inthe latter as at 3!, much in the same manner as already described in connection with the form of construction shown in Fig. 3 of the aforesaid patent. counterweight wheels 39 are also mounted on the drive shaft 38. Connecting rods til are eccentrically Journalled at their lower end to an eccentric bearing 4| which has an eccentricity opposite to that of the bearing in which the drive shaft 38 is journalled in the screen frame 30. The upper end of the connecting rods III is resiliently connected to the supporting frame 3| by means of the yoke 42 and pairs of coil springs 43. For equal eccentricities of the screen frame 3|! .and of the connecting rods with respect to the drive shaft 3!, each of the resilient supports of the connecting rods 40, consisting of the coil springs 43, are twice as still. as any one of the resilient supports "or 31 at the four corners of the screen frame 30 so that the respective forces generated in the respective resilient supports counterbalance each other and do not subject the supporting frame 3! to any unbalanced or vibrating forces.

The principle of operation of this form of apparatus is analogous to the principle of operation as previously explained in connection with Fig. 4 of the aforesaid patent. Since the screen frame 30 is pendantly supported, its gyratory motion will have no effective horizontal displacement to be transmitted to the supporting frame 3| This means that the effective displacement of the screen body in its gyratory path of travel 'will be transmitted only in a vertical direction, or along the Y axis of Fig. 4 of the aforesaid patent. Therefore, only one connecting rod for transmittingstraight line forces to counterbalance the effective forces or vector component of forces from the gyratory movement of the screen frame is necessary, and it will be noted that this connecting rod, viz., the connecting rod Ill, has only an effective displacement in a vertical direction, or also along the Y axis. But of course the direction of effective forces transmitted through the substantially vertical connecting rod 40 is opposite at all times to that of the effective forces transmitted to the screen frame 3| through the connecting rods 32 and 33. Here again, the

forces generated in the resilient supports of a gyratory body are counterbalanced by equal and opposite straight line forces generated in the resilient supports of the connecting rod.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distlnctly claim as my invention:

1. In a gyrating screen mechanism, the combination of a supporting member, a screen frame resiliently and pendantly supported on said member by means of members so constructed and arranged as to transmit forces only in a substantially vertical direction, a drive shaft-having oppositely disposed eccentrics thereon, one of said eccentrics being connected to said screen frame, a connecting rod having one end rotatably connected to the other of said eccentrics, and resilient means for connecting the other end of said connecting rod to said supporting member.

2. Ina gyrating screen mechanism, the combination of a supporting member, a screen frame,

means for supporting said frame on said member, said means so constructed and arranged as to' transmit force only in a substantially vertical direction, a drive shaft having oppositely disposed eccentrics thereon, one of said eccentrics being connected to said screen frame, substantially vertically extending connecting rod having one end directly and rotatably connected to the other of said eccentrics, and resilient means for connecting the other end of said connecting rod to said supporting member. I I

' 3. In a gyrating screen, mechanism, a screen frame, a supporting member disposed at a level above that of said screen frame, means for supporting said frame on said member, said means so constructed and arranged as'to transmit force only in a substantially vertical direction, a drive shaft having oppositely disposed eccentrics thereon, one of said eccentrics being connected to said screen frameand a substantially vertically extending connecting rod resiliently suspended from said supporting member and having its lower end pivotally connected to the other of said eccentrics.

4. In a gyrating screen mechanism, a supporting member, a screen body resiliently supported on said member by means of members so constructed and arranged as to transmit forces only in a substantially vertical direction, a drive shaft having portions eccentric with respect to each other and each eccentric to a center of rotation lying between the centers of said eccentric portions, means for connecting said screen body to one of said eccentric portions, a balancing body disposed at one side of said screen body, means connecting one end of said balancing body to the other of said eccentric portions, and means disposed at a level above said screen body for resiliently supporting said balancing member on said supporting member.

5. Ina gyrating screen mechanism, the combination of a supporting member, a gyratory screen frame resiliently supported on said memher by means of members so constructed and arranged as totransmit forces only in a substantially vertical direction, a drive shaft having oppositely disposed eccentric means, one of said eccentric means being connected to said screen frame, a connecting rod having one end resiliently connected to said supporting member at a level above said screen frame and the other end connected'to the other of said eccentric means. said connecting rod adapted to create a balancing force which balances the forces generated in the resilient supports of said screen frame as a result of its gyratory motion.

6. In a gyratory screen mechanism, the combination of a. supporting member, a screen frame, means for supporting said frame on said member, said means so constructed and arranged as to transmit forces only in a substantially vertical direction, a drive shaft having portions eccentric with respect to each other and each eccentric to a center of rotation lying between the centers of said eccentric portions, one of said eccentric portions being connected to said screen frame, a

WALTER J, PARKS. 

